From: Frank van der Linden <fllinden@amazon.com>
To: "Mkrtchyan, Tigran" <tigran.mkrtchyan@desy.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>,
Anna Schumaker <anna.schumaker@netapp.com>,
linux-nfs <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH 03/13] NFSv4.2: query the server for extended attribute support
Date: Thu, 12 Mar 2020 20:51:39 +0000 [thread overview]
Message-ID: <20200312205139.GA32293@dev-dsk-fllinden-2c-c1893d73.us-west-2.amazon.com> (raw)
In-Reply-To: <530167624.4533477.1584029710746.JavaMail.zimbra@desy.de>
On Thu, Mar 12, 2020 at 05:15:10PM +0100, Mkrtchyan, Tigran wrote:
> > + fattr4_word2_nfs42_mask = FATTR4_WORD2_NFS42_MASK;
> > +
> > + if (minorversion >= 2) {
>
> I am not sure you need this extra check as by querying for FATTR4_WORD0_SUPPORTED_ATTRS
> server already will return FATTR4_WORD2_XATTR_SUPPORT if supported.
There used to be a mount option check here, which I later removed. That
means that fattr4_word2_nfs42_mask is no longer needed, so I'll remove
that.
As for the attribute itself: I suppose the question here is what the client
should use to assume the server has RFC 8276 support:
1) The xattr_support attribute exists
2) The xattr support attribute exists *and* it's true for the root fh
Currently the code does 2) in one operation. That might not be 100%
correct - the RFC does mention that (section 8.2):
"Before interrogating this attribute using GETATTR, a client should
determine whether it is a supported attribute by interrogating the
supported_attrs attribute."
That's a "should", not a "MUST", but it's still waving its finger
at you not to do this.
Since 8.2.1 says:
"However, a client may reasonably assume that a server
(or file system) that does not support the xattr_support attribute
does not provide xattr support, and it acts on that basis."
..I think you're right, and the code should just use the existence
of the attribute as a signal that the server knows about xattrs -
operations should still error out correctly if it doesn't.
I'll make that change, thanks.
Frank
next prev parent reply other threads:[~2020-03-12 20:51 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-11 19:56 [PATCH 00/13] client side user xattr (RFC8276) support Frank van der Linden
2020-03-11 19:56 ` [PATCH 01/13] nfs,nfsd: NFSv4.2 extended attribute protocol definitions Frank van der Linden
2020-03-11 19:56 ` [PATCH 02/13] nfs: add client side only definitions for user xattrs Frank van der Linden
2020-03-11 19:56 ` [PATCH 03/13] NFSv4.2: query the server for extended attribute support Frank van der Linden
2020-03-12 16:15 ` Mkrtchyan, Tigran
2020-03-12 20:51 ` Frank van der Linden [this message]
2020-03-12 21:15 ` Frank van der Linden
2020-03-13 11:11 ` Mkrtchyan, Tigran
2020-03-13 13:50 ` Trond Myklebust
2020-03-13 14:19 ` Mkrtchyan, Tigran
2020-03-13 17:10 ` Trond Myklebust
2020-03-13 17:55 ` Frank van der Linden
2020-03-11 19:56 ` [PATCH 04/13] NFSv4.2: define limits and sizes for user xattr handling Frank van der Linden
2020-03-12 20:35 ` Schumaker, Anna
2020-03-11 19:56 ` [PATCH 05/13] NFSv4.2: add client side XDR handling for extended attributes Frank van der Linden
2020-03-12 20:49 ` Schumaker, Anna
2020-03-11 19:56 ` [PATCH 06/13] nfs: define nfs_access_get_cached function Frank van der Linden
2020-03-11 19:56 ` [PATCH 07/13] NFSv4.2: query the extended attribute access bits Frank van der Linden
2020-03-11 19:56 ` [PATCH 08/13] nfs: modify update_changeattr to deal with regular files Frank van der Linden
2020-03-11 19:56 ` [PATCH 09/13] nfs: define and use the NFS_INO_INVALID_XATTR flag Frank van der Linden
2020-03-24 6:02 ` [nfs] c5654df66d: stress-ng.msg.ops_per_sec 15.5% improvement kernel test robot
2020-03-24 16:21 ` Frank van der Linden
2020-03-11 19:56 ` [PATCH 10/13] nfs: make the buf_to_pages_noslab function available to the nfs code Frank van der Linden
2020-03-12 20:36 ` Schumaker, Anna
2020-03-11 19:56 ` [PATCH 11/13] NFSv4.2: add the extended attribute proc functions Frank van der Linden
2020-03-11 19:56 ` [PATCH 12/13] NFSv4.2: hook in the user extended attribute handlers Frank van der Linden
2020-03-11 19:56 ` [PATCH 13/13] NFSv4.2: add client side xattr caching Frank van der Linden
2020-03-12 20:39 ` Schumaker, Anna
2020-03-12 20:48 ` Schumaker, Anna
2020-03-12 19:06 ` [PATCH 00/13] client side user xattr (RFC8276) support Mkrtchyan, Tigran
2020-03-12 20:09 ` Anna Schumaker
2020-03-16 15:50 ` Frank van der Linden
2020-03-17 23:03 ` Frank van der Linden
2020-03-19 14:39 ` J. Bruce Fields
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200312205139.GA32293@dev-dsk-fllinden-2c-c1893d73.us-west-2.amazon.com \
--to=fllinden@amazon.com \
--cc=anna.schumaker@netapp.com \
--cc=linux-nfs@vger.kernel.org \
--cc=tigran.mkrtchyan@desy.de \
--cc=trond.myklebust@hammerspace.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.